Experimental Evaluation of Various Gasoline Surrogates Based on Soot Formation Characteristics

Abstract

The evaluation of soot tendency of gasoline surrogates in simple atmosphere environments is essential for understanding soot formation processes and developing accurate soot models to represent real fuel chemistry in computational fluid dynamics simulations of gasoline engines. In this work, several surrogates were evaluated on the basis of soot precursor and soot characteristics in laminar diffusion flames. The relative concentrations of polycyclic aromatic hydrocarbons (PAHs) with different ring sizes and soot were measured using laser-induced fluorescence (LIF) and laser-induced incandescence (LII) techniques. The OH and CH luminescence intensities were also recorded using an intensified charge-coupled device. The results showed that the gasoline surrogates failed to represent the formation characteristics of small-ring aromatics (320/360 nm) for gasoline flames but have certain characterization ability for large-ring aromatics (400/450 nm). The relationship between the PAH LIF signal and the toluene content is not monotonically increasing. On the basis of the relative concentrations of larger PAHs and soot, the surrogate ( 1 / 3 n-heptane, 1 / 3 isooctane, and 1 / 3 toluene) can characterize the formation characteristics of soot precursors and soot in gasoline laminar diffusion flames best. On the basis of the OH and CH luminescence intensities, the surrogate ( 1 / 3 n-heptane, 1 / 3 isooctane, and 1 / 3 toluene) can best characterize the flame structure and development of gasoline. The CH trend is consistent with the PAH trend, inferring that there exists a strong correlation between CH intensity and PAHs in the diffusion flames. As the aromatic ring number increases, its PAH LIF signal peaks at a higher position and the high concentration region gradually evolves from the flame center to the two wings of the flame, which eventually leads to the characteristic of the two-wing distribution of soot. For the binary mixture of n-heptane−toluene, the 320 nm PAH LIF signal increases monotonically with the toluene ratio. The maximum PAH LIF signals of 360−450 nm exhibit a non-monotonic tendency, which reach the peak at a 50% toluene ratio. Furthermore, there exists a tolerance in terms of the toluene mixing ratio (10%), below which the effect of toluene on larger ring aromatic (A4−A5) formation can be neglected.

Obtaining Biodiesel from Fat Extracted from Solid Waste Produced in the Fleshing Stage of Leather Manufacturing

“…Commercial gasoline was the solvent that extracted the highest amount of grease, reaching 51,50% in a 3 h period, using 150 mL of solvent and the pressurized extraction technique with solvents in liquid-gas equilibrium, as described in this work. These results are related to the mixture of hydrocarbons present in gasoline (Hua et al, 2018) which provide a lipophilic and apolar environment that favors fat recovery. These values are higher than those obtained with other techniques that have been used for the extraction of fat in this type of waste, using hexane and soxhlet equipment and achieving fat recovery values of up to 11,5%.…”

Advanced Progress and Prospects for Producing High-Octane Gasoline Fuel toward Market Development: State-of-the-Art and Outlook

“…Currently, high-octane oxygenates are used to increase the octane number of motor gasoline. , In 2019, out of 1.1 billion tons of motor gasoline produced, 127.4 million tons were oxygenates, including 86.9 million tons for bioethanol, 24.7 million tons for MTBE, and 12.1 million tons for methanol . The world production volume of TAME is significantly less than that of MTBE, which is associated with a lower octane-raising capacity and a limited resource base of isoamylenes Figure demonstrates the structure of the oxygenates market and their share in commercial gasoline.…”

“…112 The world production volume of TAME is significantly less than that of MTBE, which is associated with a lower octane-raising capacity and a limited resource base of isoamylenes. 113 Figure 9 demonstrates the structure of the oxygenates market and their share in commercial gasoline.…”